Abstract
Cloud point (CP)/lower consolute temperature (LCT) of aqueous mixture of TX-100 and a highly recognised anti-diabetic drug metformin hydrochloride (MNH) was analysed in absence/presence of NH
4
Cl, NH
4
NO
3
, (NH
4
)
2
SO
4
and (NH
4
)
2
HPO
4
. The CP values were found to be decreased with increasing concentrations of ammonium salts. Occurrence of aggregation in respective solution systems might result in declining of corresponding CP. Thermodynamic parameters (
,
and
) were calculated at CP. The appearance of positive values of Gibbs free energy (
) indicates that clouding in the studied system was thermodynamically non-spontaneous and the degree of non-spontaneity was diminished with increasing in the extents of electrolytes. The computed enthalpy (
) and entropy (
) values of the system showed negative values in cases of aq. NH
4
Cl, (NH
4
)
2
SO
4
and (NH
4
)
2
HPO
4
while the negative values tend to reduce with rise of electrolytes content. In case of aq. NH
4
NO
3
medium, the reverse results for the
and
values were detected. The
and
values in the studied system indicate the presence of electrostatic interaction between TX-100 and MNH in NH
4
Cl, (NH
4
)
2
SO
4
, (NH
4
)
2
HPO
4
media whereas the hydrophobic interactivity might play a great role within the mixture when it was placed in the NH
4
NO
3
solution.